Concave extension and rock trap for a thresher



Oct. 5, 1965 R. CLAAQ 3,209,760

CONGAVE EXTENSION AND ROCK TRAP FOR A THRESHER Original Filed Oct. 25, 1960 United States Patent 3,209,760 CONCAVE EXTENSION AND ROCK TRAP FOR A THRESHER Reinhold Claas, August-Claas-Strasse 64, Harsewinkel, Westphalia, Germany Original application Oct. 25, 1960, Ser. No. 64,950, now Patent No. 3,124,138, dated Mar. 10, 1964. Divided and this application Oct. 16, 1963, Ser. No. 316,684 Claims priority, application Germany, Oct. 29, 1959,

0,071 3 Claims. (Cl. 130-27) This invention relates to a threshing machine, more specifically to a threshing mechanism for combine harvesters, and is a division of copending application Serial No. 64,950, filed October 25, 1960, now Patent No. 3,124,138.

It is a well known fact that the performance of threshing mechanisms depends upon careful adjustment thereof to suit the nature of the crop to be threshed. To this end it is customary to drive the threshing drum at different rotary speeds and to adjust the threshing concave to the needs of the harvested crop. It is also known to interpose additional bars between the normal bars on the entry side of the threshing concave in order to achieve a satisfactory separation for instance of the awns from barley. Moreover, the openings between the bars at the entry side of the concave are occasionally closed, so that the pockets thus formed can fill up and provide a supplementary beating effect. However, expedients of this kind considerably constrict the flow of the crop through the thresher. More grain which has failed to pass between the bars of the concave therefore reaches the shaker. Losses are thus increased. The general use of concaves which are exceptionally long in the direc tion in which the crop travels does not commend itself because of the excess power needed for driving the thresher is wasted if, as such, the crop demands the use of a concave of normal length.

The object envisaged by the present invention is to overcome the aforementioned drawbacks in that the advantages that can be gained by the above-mentioned expedient are fully retained without at the same time causing waste of power and unnecessary loss through the shakers.

This object is achieved by the provision of a threshing machine, particularly threshing mechanism for combine harvesters, which comprises a threshing drum, a concave cooperating with said drum, and an extension for said concave arranged at the entry side thereof and adapted to be optionally placed into operative position for enlarging the effective area of said concave or to be removed from said operative position.

This proposal permits the number of beater bars or the number of grain loosening projections comprised in the concavethis number decisively determines the threshing effect-40 be adjusted to suit any conditions without incurring the penalties involved in too closely or not at all spacing adjacent bars or projections or undesirably raising power consumption. According to the nature of the crop which is to be threshed, the proposed extension at the entry side of the concave may be introduced or inactivated as may be desired. This result can be achieved in various ways. For instance, the concave extension may be simply detachable. For setting the machine to suit the crop which is to be handled a certain amount of work is naturally involved in fitting an extension of this kind, although little time may actually be lost in performing it. In most cases it may therefore be considered expedient, according to another feature of the invention, to mount the proposed extension permanently but adjustably in the machine. The

ice

size of the effective concave area may then be varied by manipulating simple setting controls.

. Extensions which can thus be optionally moved into operative and inoperative positions may be contrived in diverse ways. For instance, an optionally activatable concave extension at the entry side of the concave may be associated with a stone catcher trough provided in the threshing mechanism and contrived in a suitable way for the extension to be lowered into the same when displaced into inactive position. Alternatively, the optionally activatable extension may be suitably designed to form a stone catching trough or part of a stone catching trough when it is retracted into an inoperative position. This will generally provide a particularly compact and space-saving design. However, in such an arrangement the stone catcher trough will naturally be available only when threshing proceeds and the extension is not used to enlarge the surface area of the concave.

The extension may be adjustably fitted to the machine in various ways. In one possible form of construction the extension may be tiltably mounted about its longitudinal axis and thus adapted to be rotated into an operative or into an inoperative position and, in the latter position, the extension may be contrived to form a stone catcher trough or part of such a trough. Alternatively, the extension may be slidably displaceable in translatory motion, and any suitable sliding guide means may be provided to this end. For instance the extension may be slidably mounted in special guideways in the form of slots in a supporting part of the frame of the machine. In another feasible form of construction the extension may be mounted on deflectable arms or the like and perform a combined sliding and tilting motion.

The optionally activatable concave extension may itself be of different forms of construction. Its effective surface may be formed in the same manner as the concave proper in the form of a grating or, in given circumstances, it may be preferred to provide an extension Without openings but formed with a surface having projecting embossments which have a beating effect for detaching the grain from the ears.

The setting means for activating and inactivating a concave extension as proposed by the present invention may likewise be contrived in various ways. The provision of separate manually operable control means is a simple solution. However, it may sometimes be considered convenient to combine the setting means of the concave with the control means of the concave extension.

Several preferred embodiments of the invention will now be described by Way of example and with reference to the accompanying drawings, in which:

FIG. 1 is a side elevational view, partly in section, of a threshing machine;

FIG. 2 is a side elevational view, on a larger scale, of a mechanism contrived in the manner proposed by the present invention, showing a concave extension in operative position;

FIG. 3 is a similar representation of the embodiment according to FIG. 2, showing the extension in retracted inoperative position;

FIG. 4 is a perspective view of part of a concave with an extension according to FIG. 2 in operative position at the entry side of the concave;

FIG. 5 is a side elevational view, similar to that in FIG. 2 of another embodiment of a concave extension according to the invention at the entry side of the concave in operative position;

FIG. 6 is a similar representation of the extension illustrated in FIG. 5 but in retracted inactivated position; and

FIG. 7 is a representation similar to that in FIG. 4 of a concave with an extension according to FIG. 6 at the entry side of the concave in inoperative position.

With reference now to FIG. 1 which illustrates a selfpropelled combine harvesting machine, a frame 10 is mounted on pairs of wheels 11 and 12, the forward end of said frame It carrying a cutter assembly 13 which delivers the crop on endless conveyor means 14 to a thresher likewise mounted within said frame. The latter substantially comprises a threshing drum 15 and a concave 16 cooperating therewith. If required, an extension 17 can be attached to the entry side of said concave. Behind the drum 15 is a beater 18 which in conventional manner revolves in the same direction as the threshing drum above a screen 19 which bridges the distance between the concave 16 and a straw shaker 20. The drum 15 and the beater 18 are rotatably mounted on parallel axles preferably between opposite side walls of the frame 10. Most of the grain rubbed out of the ears drops through the concave 16 and the screen 10 on to a dressing shoe 21 which may be constructed in any conventional manner known to the art. The straw passes out on to the shaker 20 where the remaining grain is shaken out. After leaving the shaker 20 the straw may be delivered to a baling press 22. The frame 10 of the combine harvester which is driven by an internal combustion engine 23 is surmounted by a bagging stand 24 to which the grain is delivered in conventional manner. The machine frame 10 is also equipped with a cab 25 for the driver.

In the embodiment shown in FIGS. 2 to 4, an extension 40 is tiltably mounted at the leading end of the con cave 16. The extension 40 itself in this form of construction is substantially box-shaped with an unperforated surface provided with projecting embossments 41 which have a similar action on the crop as the bars. In FIGS. 2 and 4 the extension 40 is shown in operative position in which it forms a prolongation of the concave 16, for instance, for threshing barley and like crops. In FIG. 3 the extension 40 is shown tilted into inverted position in which it does not participate in the threshing action. However, in this position it forms a stone catcher trough. In this form of construction tipping of the concave extension 40 about pivot pins 42 between its active and inactive positions may be effected by manually operable levers. Since it is necessary that the extension be movable toward and away from the threshing drum together with the concave, it may be desirable to combine the manually operable levers with the means for setting the concave by providing a rod linkage 43, 44. Such linkages will simplify control. Thus the extension 40 moves toward and away from the threshing drum together with the concave, whereas tilting of the extension is independent of any adjustment of the concave 16 itself.

An example of a suitable linkage is shown in the drawing. A control lever 45 is secured to the harvester pivotable about a pivot point 50. A pair of arms 52 and 53 are pivoted at 51 to lever 45. At their lower ends the arms 52 and 53 are turnably secured to the front end and back end of the concave, respectively, at points 54 and 55. A third arm 62 is pivotally secured to arm 53 and is connected with a lever 58 via a bore 59 provided in the same. Lever 58 is rigidly connected to the pivots 42 by which the extension is turnably mounted. Thus, manipulation of lever 45 will move both the concave and the extension closer to, or farther away from, the drum. On the other hand, tilting of the ex tension by 180 about the pivots 42 is accomplished by disconnecting arm 53 from bore 59, turning the extension, swinging arm 53 into the position shown in FIG. 3, and reconnecting it with bore 59.

The further embodiment shown in FIGS. to 7 resembles the form of construction according to FIGS. 2 to 4 inasmuch as a concave extension 40 is likewise provided with an unperforated surface formed with projecting embossrnents 41. However, in this case the concave extension 40 is not tiltable about its longitudinal axis but shiftable in substantially translatory motion by being mounted on pins 46 which slidably engage appropriate guide means, such as slots 47, in members afiixed to the frame. In this form of construction the concave extension 40 may operate as such when in the position shown in FIG. 5, or it may be retracted as illustrated in FIGS.

6 and 7 when it forms at least part of a stone catcher trough. Control of the concave extension 40 may likewise be by the rod linkage 44- coupled with the means 45 for setting the concave 16 if this should be considered desirable for reasons of more convenient control. Nevertheless, provision is likewise made for independently adjusting the concave and the extension.

The embodiments that have been described are understood to be merely illustrative of the invention. They are not intended to limit its scope. Various alternative forms of construction may be devised. The optionally operatable extension of the concave illustrated in FIGS. 2 to 4 and 5 to 6, might likewise be in the form of a grating. If desired, and as may be considered convenient, the concave extension may be of divided construction or consist of integral sheet metal parts or of a single piece casting. Moreover, a plurality of concave extensions of different construction for optional use may be provided for use in a threshing machine to permit the machine to be more carefully adjusted to any particular set of working conditions.

I claim:

1. A threshing mechanism, particularly for combine harvesters comprising, in combination, support means; a threshing drum on said support means;

feeding means on said support means forwardly of said drum said feeding means having a delivery end directed toward said drum for feeding material to be threshed thereto, said delivery end being spaced from said drum by a fixed distance;

a concave partly surrounding said drum and having an active surface of a given length facing said drum spaced therefrom by a given minimum distance con siderably smaller than said fixed distance and cooperating therewith, said concave having a receiving end rearwardly spaced from said delivery end of said feeding means and forming a gap therewith;

box-shaped extension means for increasing said length of said surface and being located between said delivery end of said feeding means and said receiving end of said concave, said extension means having a transverse wall surface bridging said gap between said delivery end of said feeding means and said receiving end of said concave;

and means at said support means mounting said extension means turnable about an axis extending substantially parallel to said transverse wall surface between an active position in which said surface of said extension means forms a continuation of said active surface of said concave for increasing the active length thereof, and wherein said surface forms with said drum a concave entry of a predetermined size for said feeding means to feed into and an inactive position in which said extension means is turned substantially through about said axis and in which said transverse wall surface is downwardly displaced with respect to said receiving end of said concave to increase the size of said concave entry so that stones carried by said feeding means cannot become jammed at said entry, and simultaneously form part of a stone catching means ahead of said receiving end of said concave while continuously bridging said gap without increasing the active length of said concave.

2. A threshing mechanism, particularly for combine harvesters comprising, in combination, support means; a

threshing drum;

feeding means on said support means forwardly of said drum, said feeding means having a delivery end directed toward said drum for feeding material to be threshed thereto, said delivery end being spaced from said drum by a fixed distance;

forms a stone catcher ahead of said receiving end of said concave while continuously bridging said gap without increasing the active length of said concave.

ing means and forming a gap therewith, said concave being movable toward and away from said drum between said given minimum distance and a distance exceeding said given minimum distance;

concave partly surrounding said drum and having box-shaped extension means having an open side and an active surface of a given length facing said drum being located between said delivery end of said spaced therefrom by a given minimum distance confeeding means and said receiving end of said considerably smaller than said fixed distance and cocave, said extension means having a transverse Wall operating therewith, said concave having a receiving surface for bridging said gap between said delivery end rearwardly spaced from said delivery end of said 10 end of said feeding means and said receiving end of feeding means and forming a gap therewith; said concave for increasing said length of said surbox-shaped extension means for selectively increasing face;

said length of said surface and being located between means at said support means mounting said box-shaped said delivery end of said feeding means and said reextension means turnable about an axis substantially ceiving end of said concave, said extension means parallel to said transverse wall surface between an having a transverse wall surface formed with a pluactive position in which said surface of said extenrality of projections and bridging said gap between sion means forms a continuation of said active sursaid delivery end of said feeding means and said reface of said concave for increasing the active length ceiving end of said concave; thereof and wherein said surface forms with said and means at said support means mounting said boxdrum a concave entry of a predetermined size for shaped extension means turnable about an axis exsaid feeding means to feed into, and an inactive tending substantially parallel to said transverse wall position in which said extension means is turned subsurface between an active position in which said surstantially through 180 about said axis and in which face of said extension means forms a continuation said transverse wall surface is downwardly spaced of said active surface of said concave for increasing from said receiving end of said concave to increase the active length thereof and wherein said surface the size of said concave entry so that stones carried forms with said drum a concave entry of a predeterby said feeding means cannot become jammed at mined size for said feeding means to feed into, and said entry, and simultaneously said open side of an inactive position in which said extension means said box-shaped extension means faces upwardly and is turned substantially through 180 about said axis said extension means forms a stone catcher ahead and in which said transverse wall surface is downof said receiving end of said concave while conwardly spaced from said receiving end of said continuously bridging said gap without increasing the accave to increase the size of said concave entry so tive length of said concave, said mounting means inthat stones carried by said feeding means cannot eluding a pair of bearing brackets respectively fixed become jammed at said entry, and simultaneously to opposite sides of said receiving end of said concave and projecting therefrom toward said delivery end of said feeding means, and pivot pins extending along said axis fixed to said extension means and 3. A threshing mechanism, particularly for combine harvesters comprising, in combination, support means; a threshing drum on said support means;

feeding means on said support means forwardly of said drum, said feeding means having a delivery end directed toward said drum for feeding material to be threshed thereto, said delivery end being spaced from said drum by a fixed distance;

turnably mounted in said bearing brackets; and means for moving said concave toward and away from said drum in dependence upon the type of material to be threshed.

References Cited by the Examiner UNITED STATES PATENTS a concave partly surrounding said drum and having an 2 gzgig active surface of a given length facing said drum 2,959,175 11/60 Oberholtz et a1 130 27-9 spaced therefrom by a given minimum distance considemfly Smaller. than. said fixed disiance 9 ANTONIO F. GUIDA, Acting Primary Examiner. operating therewith, said concave having a receiving end rearwardly from said delivery end of said feed- GRAHAM R mer. 

1. A THRESHING MECHANISM, PARTICULARLY FOR COMBINE HARVESTERS COMPRISING, IN COMBINATION, SUPPORT MEANS; A THRESHING DRUM ON SAID SUPPORT MEANS; FEEDING MEANS ON SAID SUPPORT MEANS FORWARDLY OF SAID DRUM SAID FEEDING MEANS HAVING A DELIVERY END DIRECTED TOWARD SAID DRUM FOR FEEDING MATERIAL TO BE THRESHED THERETO, SAID DELIVERY END BEING SPACED FROM SAID DRUM BY A FIXED DISTANCE; A CONCAVE PARTLY SURROUNDING SAID DRUM AND HAVING AN ACTIVE SURFACE OF A GIVEN LENGTH FACING SAID DRUM SPACED THEREFROM BY A GIVEN MINIMUM DISTANCE CONSIDERABLY SMALLER THAN SAID FIXED DISTANCE AND COOPERATING THEREWITH, SAID CONCAVE HAVING A RECEIVING END REARWARDLY SPACED FROM SAID DELIVERY END OF SAID FEEDING MEANS AND FORMING A GAP THEREWITH; BOX-SHAPED EXTENSION MEANS FOR INCREASING SAID LENGTH OF SAID SURFACE AND BEING LOCATED BETWEEN SAID DELIVERY END OF SAID FEEDING MEANS AND SAID RECEIVING END OF SAID CONCAVE, SAID EXTENSION MEANS HAVING A TRANSVERSE WALL SURFACE BRIDGING SAID GAP BETWEEN SAID DELIVERY END OF SAID FEEDING MEANS AND SAID RECEIVING END OF SAID CONCAVE; AND MEANS AT SAID SUPPORT MEANS MOUNTING SAID EXTENSION MEANS TURNABLE ABOUT AN AXIS EXENDING SUBSTANTIALLY PARALLEL TO SAID TRANSVERSE WALL SURFACE BETWEEN AN ACTIVE POSITON IN WHICH SAID SURFACE OF SAID EXTENSION MEANS FORMS A CONTINUATION OF SAID ACTIVE SURFACE OF SAID CONCAVE FOR INCREASING THE ACTIVE LENGTH THEREOF, AND WHEREIN SAID SURFACE FORMS WITH SAID RUM A CONCVE ENTRY OF A PREDETERMINED SIZE FOR SAID FEEDING MEANS TO FEED INTO AND AN INACTIVE POSITION IN WHICH SAID EXTENSION MEANS IS TURNED SUBSTANTIALLY THROUGH 180* ABOUT SAID AXIS AND IN WHICH SAID TRANSVERSE WALL SURFACE IS DOWNWARDLY DISPLACED WITH RESPECT TO SAID RECEIVING END OF SAID CONCAVE TO INCREASE THE SIZE OF SAID CONCAVE ENTRY SO THAT STONES CARRIED BY SAID FEEDING MEANS CANNOT BECOME JAMMED AT SAID ENTRY, AND SIMULTANEOUSLY FORM PART OF A STONE CATCHING MEANS AHEAD OF SAID RECEIVING END OF SAID CONCAVE WHILE CONTINUOUSLY BRIDGING SAID GAP WITHOUT INCREASING THE ACTIVE LENGTH OF SAID CONCAVE. 